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Number of nX3 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 1, 2 or 3 neighboring 1s.
1

%I #4 Jan 02 2018 15:05:44

%S 4,43,231,1421,9033,55706,346032,2151932,13364992,83036263,515911384,

%T 3205231551,19913717003,123721335945,768662962676,4775598530205,

%U 29670139081754,184336490377417,1145257318539730,7115326466070793

%N Number of nX3 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 1, 2 or 3 neighboring 1s.

%C Column 3 of A297654.

%H R. H. Hardin, <a href="/A297649/b297649.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 3*a(n-1) +9*a(n-2) +60*a(n-3) +51*a(n-4) +54*a(n-5) -303*a(n-6) -336*a(n-7) -234*a(n-8) +316*a(n-9) +264*a(n-10) -144*a(n-11)

%e Some solutions for n=6

%e ..1..1..1. .0..0..0. .0..1..1. .0..0..1. .1..1..0. .0..0..0. .0..1..0

%e ..1..1..0. .0..1..1. .1..0..1. .1..1..0. .0..0..1. .0..1..0. .0..0..1

%e ..0..0..0. .0..0..0. .1..1..0. .0..0..0. .1..1..1. .0..1..1. .1..0..1

%e ..0..0..0. .0..0..0. .0..1..0. .1..1..1. .0..0..0. .0..1..1. .0..1..0

%e ..1..1..1. .1..1..0. .0..0..1. .0..1..1. .1..1..0. .0..1..0. .0..1..1

%e ..0..1..0. .1..0..1. .0..1..1. .0..1..0. .1..0..0. .1..0..1. .0..0..0

%Y Cf. A297654.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jan 02 2018